Operator cabs have been provided at the front of a harvester between the front wheels thereof and adjacent to a transversely mounted grain tank, one such harvester being shown in U.S. Pat. No. 2,834,633. Top shields for vehicles are shown in U.S. Pat. Nos. 2,643,912 and 2,643,913 and also in French Pat. No. 1,305,885. U.S. Pat. No. Re. 29,123 illustrates a cab with lights mounted in the front of a roof structure.